%SETNLAB Set label indices (numeric labels) directly
%
%    A = SETNLAB(A,NLAB,J)
%
% Resets the values of A.NLAB(J) to NLAB. Note that NLAB points
% to the labels defined in A.LABLIST. Values of NLAB <= 0 are
% stored but treated as missing labels. For crisp labels only.
